Jennifer was known as “the crazy lady.” But that didn’t prevent her from been able to purchase a gun she used to murder six people at a mail-handling facility along with a former neighbor. Jennifer was paranoid and obsessed with racial hatred, but despite bizarre behavior at home and at work, apart from a 3 day stint in a psychiatric facility it’s unknown whether she received any therapy there or anywhere else. Criminologists have called Jennifer San Marco's rampage the worst workplace shooting by a woman in United States history.